**Question:** In Parkinsonism, what is not present -

A. Hyperreflexia
B. Dyskinesias
C. Orthostatic hypotension
D. Bradykinesia

**Correct Answer:** D. Bradykinesia

**Core Concept:**
Parkinsonism is a neurological disorder characterized by a combination of motor symptoms, including tremors, rigidity, and bradykinesia (slowness of movement). Parkinson's disease is the most common cause of Parkinsonism, but other causes include medications, infections, and toxins. Bradykinesia is the clinical feature of reduced movement speed, which is caused by the loss of dopaminergic neurons in the substantia nigra.

**Why the Correct Answer is Right:**
Bradykinesia is the core motor feature of Parkinsonism, particularly in Parkinson's disease. In Parkinson's, the degeneration of dopaminergic neurons in the substantia nigra leads to a decrease in dopamine levels, which results in bradykinesia. This motor symptom is less severe than tremors, rigidity, and postural instability.

**Why Each Wrong Option is Incorrect:**

A. Hyperreflexia refers to exaggerated reflexes, which is an overactive spinal reflex response. This is unrelated to the motor symptoms of Parkinsonism and is more commonly seen in conditions like spinal cord injury or neurological disorders affecting the descending motor pathways.

B. Dyskinesias are involuntary, irregular, and often rapid movements that can be seen in Parkinson's disease during the later stages. Unlike bradykinesia, dyskinesias are not a typical feature of early Parkinsonism.

C. Orthostatic hypotension is a decrease in blood pressure upon standing or changing from a supine position. This is a cardiovascular, not a motor, symptom and is more commonly associated with autonomic nervous system dysfunction, rather than Parkinsonism.

**Clinical Pearl:**
Understanding the motor symptoms of Parkinsonism, including bradykinesia, tremors, rigidity, and postural instability, helps in differentiating it from other neurological conditions with overlapping symptoms. In Parkinson's disease, motor symptoms typically develop gradually, while hyperreflexia, dyskinesias, and orthostatic hypotension may be seen in different conditions.